Sun Media has learned the Senators owner was so furious with being forced to shell out a $4-million bonus to Dany Heatley, who refused to accept a trade to the Edmonton Oilers on July 1, he has filed a grievance asking for his money back.

An NHL executive confirmed last night Melnyk filed the paperwork early in the summer, not long after Heatley wouldn’t lift his no-movement clause before the bonus was paid.

Sources say the grievance — which will be defended on Heatley’s behalf by the NHL Players Association — is pending and no hearing date has been set. Indications are it could take a while to be heard, especially with the frazzled state of the union and the departure of its executive director Ian Penny on Friday.

Indications are Melnyk isn’t convinced he can be successful, but after handing over a whopping $14 million to Heatley only 12 months into a seven-year contract extension, the Senators won’t fork over the cash without a fight.

“I don’t think Melnyk really expects to get his money back,” said a league executive. “I do think he wants to cause Heatley some hardship because he caused plenty of problems for the Senators in the summer.”

Sources say Melnyk contends in the paperwork filed at the NHL’s New York headquarters, that Heatley’s camp — including agents J.P. Barry and Stacey McAlpine — gave the Senators permission to speak with the Oilers and the two-time, 50-goal scorer should have accepted the deal to Edmonton.

It’s believed Melnyk not only claims the decision by Heatley to kill the deal cost him $4 million, it also hurt the club’s ability to sell season tickets because of the uncertainty in the Senators camp.

Heatley was dealt to the San Jose Sharks in September.

Barry couldn’t be reached for comment, but league executives believe Melnyk is patient enough to battle this matter to the finish.

“He doesn’t like to lose. He’s going to have to be patient here because this could take a while and there is some merit to his case,” said a league executive. “Something like this could take two years to be worked out. I’m not sure this will bother Heatley, though.”

Once the Edmonton deal died, Senators GM Bryan Murray found it difficult to put another trade together. The Senators decided they had to make a deal when Heatley showed up for training camp defiant and unwilling to bend on his demand.

The league executive said there’s a chance the Sharks could be forced to pay the bonus back to Melnyk if he wins his grievance. San Jose made an offer for Heatley at the NHL draft in June, but only wanted to complete the deal on July 2 — after the bonus had been paid.

“The issue for Melnyk is going to be the fact that Heatley had that ‘no movement’ clause. That allows him to veto a trade,” said the executive. “It’s going to be difficult for the Senators to argue that fact whether they like it or not.”

The move to San Jose hasn’t hurt Heatley. He has 17 points, including nine goals, in 17 games with the Sharks.